It is well-known that for various reasons the nails, and, principally women's nails, often exhibit surface uneveness, have a marked tendency to crack and to split, exhibit transitory or chronic tarnishing, exhibit partial or extensive softening of the whole of the body of the nail and, in a general manner, have an abnormal fragility.
Thus, the nails exhibit an unaesthetic and awkward appearance and are a source of inconvenience and multiple unpleasantness.
In order to reinforce the nails and also to protect them vis-a-vis an attack by external agents, it has previously been recommended to use various different methods which employ compositions based either on protein crosslinking agents so as to reinforce the keratinic system of the nails, such crosslinking agents including, for example, formol or certain of its derivatives, such as bis-(hydroxymethyl) ethylene thiourea, or on agents which function essentially as nutratives such as, for example, fatty acids, cystine, cholesterol, S-carboxymethylcysteine or even collagen extracts.
The use of such crosslinking agents or nutrative agents do not provide, however, acceptable results. Further, the use of these types of agents create certain disadvantages. In particular, products based on formol or its derivatives can cause certain allergic reactions.